When it comes to optimizing traffic to your website, plenty of reports would have you believe that social media is the only field worth plowing. But a new Adobe study shows that Google searches remain a dominant force—so much so, that even small tweaks to its algorithm can cause immediate and significant changes in Web traffic.

The company has a history of intentionally punishing or rewarding websites, based on whether they align with its vision or not. Most recently, it decided to lower rankings for websites that weren’t mobile-optimized, such as those displaying large text that didn’t wrap to fit smartphone screens.

The change wound up not being so little after all.

When Google, which owns 70.8% of the global search engine market, decided to focus on phone-friendly websites, the shift wound up undercutting traffic and raising the overall cost of website operation. The report calls it the Google “mobilegeddon.”

KO’ed By Mobilegeddon

According to the report, which tracked 5,000 websites [PDF], Google’s shift shrank traffic to some sites up to nearly 10% in just 2 months after it implemented the policy. That may not sound like much, but for high-volume sites, that can amount to a severe drop-off.

Publishers didn’t just buy more ads; they wound up paying more per interaction, with the “cost-per-click” of ads rising 16%.

Everyone knows Google owns Web searches. (They don’t call it a search giant for nothing.) But scenarios like this illustrate how deep its influence can go.

Woe Be To Anyone Who Doesn’t Think Like Google

In past years, Google has tweaked its algorithm to punish content farms, such as Demand Media’s How.com. The site features popular headlines, but the tech company believes it lacks substantive information.

In the future, Google reportedly plans to prioritize websites that have scientifically validated facts, rather than speculation—especially when it comes to health-related information. This could have a big impact on fringe communities that lay outside popular opinion, like anti-vaccination activists. Granted, that can be either good or bad news, depending on your point of view.

But the move may also keep educational sites about Eastern medicine, holistic healing and alternative therapies in the shadows, away from the Google spotlight.

The numbers in the “mobilegeddon” report matter less than the fact it managed to quantify how Google can broadly influence the way we find information or media. Let it be a lesson: Those who want to curry favor with the search giant will align with their priorities with it.

In other words, woe be to any site that ignores Google’s priorities. You could be de-ranked into obscurity.

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